Emergency medical teams arrived at tsunami-hit Niuatoputapu island yesterday, the first outside aid for Tongan victims since the early-morning disaster two days ago.

The death toll for this remote settlement 500km north of the country's main island, Tongatapu, is nine.

Four residents with serious injuries were flown out to Tonga's capital, Nuku'alofa, only yesterday because damage to Niuatoputapu's sole airstrip meant no craft could land immediately after the disaster.

Tongan Government spokesman Alfred Soakai, who had flown over the island, said 90 per cent of homes had been destroyed and the hospital had been seriously damaged.

Two of the island's villages, Hihifo and Falehau, bore the brunt of three tidal waves, some 6m high, which hit at three-minute intervals after the 8.3-magnitude earthquake. Vaipoa village remained relatively unharmed.

Just over 1000 people live on Niuatoputapu, which sits close to the Samoan border. It is isolated by the expensive cost of infrequent transport to the island.

That isolation has been exacerbated this week as the tsunami severed all telecommunications infrastructure.

Because aid workers were unable to fly directly to the island, a Tonga Defence Services patrol boat loaded with food, medical supplies and tents was sent north from Tongatapu, arriving about 6pm yesterday.

Journalist Pesi Fonua, who was also on the Government-chartered flight over the island, saw scenes of devastation. Coastal villages have all but disappeared, with murky water lapping at shores awash with debris.

"It looked like everything had been flushed out to sea," said Fonua.

"The amazing thing was that we saw very few people."

"We flew around a number of times but there was very little movement, I counted about five people."

It was heartbreaking not being able to land, he said.

"Those people must have been wondering what on earth was happening. We could tell that they were in distress and were expecting general assistance."

Clean water remains a critical issue. Storage tanks are either unusable or were destroyed.

A radio clothing and food drive started yesterday morning in Nuku'alofa and a French frigate, which is on a goodwill trip to the capital, has been formally asked to take supplies to Niuatoputapu.